Word count is probably something readers don't pay much attention to, other than wishing a book was longer because they enjoyed the characters and/or plot or wishing it was shorter because the author digressed too much.
I have been fortunate with the Black Swamp Mysteries series and many of my stand-alones because I've been given the freedom to tell the story without being overly concerned about the word count. But last year I began writing for a different venue in which word count was critical; I was told it could be as short as 65,000 words but absolutely no longer than 85,000 words.
The result: I found I've been tightening my writing and the readers are enjoying it.
My previous books had ranged from 70,000 words to around 120,000. While no one complained about the lengthier book, shorter books are less expensive to produce and take up less inventory space (my publishers have thus far all been traditional, not print-on-demand.) Writing shorter books also allowed me to write three novels last year, as the average length for each was around 80,000 words.
Do you often wish a book was longer? Or do you wish sometimes the author had tightened things up so it was shorter and easier to read?